Drain apparatus

ABSTRACT

A drain apparatus includes a drain body, a stem, a stopper and at least one torsion spring. The drain body has a drain passage therethrough and a frame radially extending across the drain passage. The stem has a shank and one end connected to the frame. The shank has a chamber, at least one first aperture and at least one second aperture opposite to the first aperture. The stopper is configured to seal the drain passage of the drain body, and has a tube extending therefrom. The tube of the stopper is movably mounted around the stem. The torsion spring is disposed in the chamber of the shank. The torsion spring has two ends laterally engaged in the first aperture and the second aperture of the shank to abut against an inner wall of the tube of the stopper.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a drain apparatus, and more particularly to a stem assembly of a drain apparatus.

2. Description of Related Art

As discloses in U.S. Pat. No. 4,597,112, a conventional drain apparatus has an annular body and a closure member which may be seated against the inlet end of a drain passage through the body. A stem extends from the closure member through a guide element within the drain passage and a spring acts between the stem and guide element to apply sealing pressure to the seated closure member. The closure member may be manually pulled outwardly from the body against the force of the spring and turned angularly to latch the member at an open position when fluid is to be drained. The positive sealing force generated by the spring minimizes or avoids leakage under conditions where the forces of gravity and pressure from overlying liquid may be inadequate for the purpose.

There are still some shortcomings of the conventional drain apparatus, such as elastic fatigue of the spring may be occurred during a long-term utilization.

The present invention has arisen to mitigate and/or obviate the disadvantages of the conventional drain apparatus.

SUMMARY OF THE INVENTION

The main objective of the present invention is to provide an improved stem assembly of a drain apparatus.

To achieve the objective, a drain apparatus comprises a drain body, a stopper, a stem and at least one torsion spring. The drain body has a drain passage therethrough and a frame radially extending across the drain passage. The stem has a shank and two connecting portions at opposite ends of the shank, one of the two connecting portions connected to the frame of the drain body. The shank has a chamber therein, at least one first aperture defined in a side of the shank, and at least one second aperture opposite to the first aperture. The first aperture and the second aperture each communicates with the chamber of the shank. The stopper is configured to seal the drain passage of the drain body, and has a tube extending therefrom. The tube is movably mounted around the stem so that the stopper is axially movable relative to the drain body.

Specifically, the torsion spring is disposed in the chamber of the shank. The torsion spring has two ends laterally engaged in the first aperture and the second aperture of the shank, and protruded from an outer periphery of the shank to abut against an inner wall of the tube of the stopper.

Moreover, each of the connecting portions of the stem defines an external thread at an outer periphery thereof. The frame of the drain body has a threaded hole in a center thereof for being connected with the respective connecting portion of the stem. The torsion spring has a coil portion and two hook portions extending from two ends of the coil portion. The two hook portions are slightly narrower than the first aperture and the second aperture of the shank, and the two hook portions are partly received in the first aperture and the second aperture of the shank respectively. The stopper further has a knob at a top thereof and a flange defined between the tube and the knob. The shank of the stem defines a lock hole in the outer periphery thereof. A bolt is fastened in the lock hole. The tube of the stopper defines a slot therethrough for accommodating the bolt.

Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a drain apparatus in accordance with a preferred embodiment of the present invention;

FIG. 2 is an exploded perspective view of the drain apparatus shown in FIG. 1;

FIG. 3 is a perspective view of a stem of the drain apparatus shown in FIG. 2, wherein two torsion springs are disposed in the stem;

FIG. 4 is a cross-sectional view of the drain apparatus along line IV-IV of FIG. 1;

FIG. 5 is a cross-sectional view of the drain apparatus along line V-V of FIG. 1; and

FIG. 6 illustrates that a stopper is raised relative to a drain body.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-3, a drain apparatus in accordance with a preferred embodiment of the present invention comprises a drain body 1, a stopper 2, a stem 3 and two torsion springs 4. The drain body 1 has a drain passage 11 therethrough and a frame 12 radially extending across the drain passage 11. The stem 3 has a shank 31 and two connecting portions 32 at opposite ends of the shank 31. One of the two connecting portions 32 is connected to the frame 12 of the drain body 1. The shank 31 has a chamber 311 therein, two first apertures 312 defined in a side of the shank and spaced a distance apart, and two second apertures 313 defined in opposite side of the shank 31 and corresponding to the two first apertures 312. The two first apertures 312 and the two second apertures 313 each communicates with the chamber 311 of the shank 31. The stopper 2 is configured to seal the drain passage 11 of the drain body 1, and having a tube 21 extending therefrom. The tube 21 is movably mounted around the stem 3 so that the stopper 2 is axially movable relative to the drain body 1.

As shown in FIG. 3, the two torsion springs 4 are disposed in the chamber 311 of the shank 31. Each of the two torsion springs 4 has two ends laterally engaged in the respective first aperture 312 and the respective second aperture 313 of the shank 31, and protruded from an outer periphery of the shank 31 to abut against an inner wall of the tube 21 of the stopper 2. The two torsion springs 4 are configured to increase a friction force between the inner wall of the tube 21 of the stopper 2 and the shank 31 of the stem 3.

Referring to FIGS. 2-3, each of the connecting portions 32 of the stem 3 defines an external thread 321 at an outer periphery thereof. The frame 12 of the drain body 1 has a threaded hole 121 in a center thereof for being connected with the respective connecting portion 32 of the stem 3 so that the tube 21 of the stopper 2 is axially movable relative to the drain body 1, as shown in FIGS. 5-6.

Specifically, each torsion spring 4 has a coil portion 41 and two hook portions 42 extending from two ends of the coil portion 41, as shown in FIG. 2. A bending portion 43 is defined between the respective loop portion 42 and the coiling portion 41. Wherein, the two hook portions 42 are slightly narrower than the respective first aperture 312 and the respective second aperture 313 of the shank 31, so that the two hook portions 42 of each torsion spring 4 could be protruded from the outer periphery of the shank 31; meanwhile, the two hook portions 42 are respective and partly received in the respective first aperture 312 and the respective second aperture 313 of the shank 31.

Furthermore, as shown in FIGS. 1-2, the stopper 2 further has a knob 22 at a top thereof and a flange 23 defined between the tube 21 and the knob 22. A gasket 6 is disposed under the flange 23 of the stopper 2 for sealing an opening of the drain passage 11 of the drain body 1. As shown in FIG. 4 and referring to FIG. 2, the shank 31 of the stem 3 defines a lock hole 314 in the outer periphery thereof. A bolt 5 is fastened in the lock hole 314. The tube 21 of the stopper 2 defines a slot 211 therethrough for accommodating the bolt 5. Therefore, the stopper 2 could be positioned between an open position and a close position, as shown in FIGS. 5-6.

Although embodiments of this invention have been fully described with reference to the accompanying drawings, it is to be understood that various modifications can be made by those skilled in the art without departing from the scope of the invention as hereinafter claimed. 

What is claimed is:
 1. A drain apparatus, comprising: a drain body having a drain passage therethrough and a frame radially extending across the drain passage; a stem having a shank and two connecting portions at opposite ends of the shank, one of the two connecting portions connected to the frame of the drain body, the shank having a chamber therein, at least one first aperture defined in a side of the shank, and at least one second aperture defined in opposite side of the shank and corresponding to the first aperture, the first aperture and the second aperture each communicating with the chamber of the shank; a stopper configured to seal the drain passage of the drain body, and having a tube extending therefrom, the tube movably mounted around the stem so that the stopper is axially movable relative to the drain body; and at least one torsion spring disposed in the chamber of the shank, the torsion spring having two ends laterally engaged in the first aperture and the second aperture of the shank, and protruded from an outer periphery of the shank to abut against an inner wall of the tube of the stopper.
 2. The drain apparatus as claimed in claim 1, wherein each of the connecting portions of the stem defines an external thread at an outer periphery thereof; and the frame of the drain body has a threaded hole in a center thereof for being connected with the respective connecting portion of the stem.
 3. The drain apparatus as claimed in claim 1, wherein the torsion spring has a coil portion and two hook portions extending from two ends of the coil portion; the two hook portions are slightly narrower than the first aperture and the second aperture of the shank; and the two hook portions are partly received in the first aperture and the second aperture of the shank respectively.
 4. The drain apparatus as claimed in claim 1, wherein the stopper further has a knob at a top thereof and a flange defined between the tube and the knob.
 5. The drain apparatus as claimed in claim 1, wherein the shank of the stem defines a lock hole in the outer periphery thereof; a bolt is fastened in the lock hole; and the tube of the stopper defines a slot therethrough for accommodating the bolt.
 6. The drain apparatus as claimed in claim 4 further comprising a gasket disposed under the flange of the stopper. 